Triple action power press



Feb. 5, 1935. A SEIDEL ET AL 1'',989,827

TRIPLE ACTION POWER PRESS Filed May 5. 1954 6 Sheets-Sheet l *4" H W fi /6% Feb. 5, 1935.

A. SEIDEL ET AL TRIPLE ACTION POW ER PRESS Filed May 5, 1954 6 Sheets-Sheet 2 1935 A SEIDEL ET AL 1,989,827

TRIPLE ACTION POWER PRESS Filed May 3, 1934 6 Sheets-Sheet 3 V Feb. 5, 1935. A. SEIDEL ET AL TRIPLE ACTION POWER PRESS Filed May 5, 1934 6 Sheets-Sheet 4 Feb. 5, 1935.

Tlcl S FLOWER PLUNGER STROKE H PLUNGER STROKE- I DRAW REDRAW TRIPLE ACTION POWER PRESS Filed May 3, 1934 6 Sheets-Sheet -5 III :; hcifl 5 53 50 0 HYDRAULIC i CYLINDER VALVE BEING- RETURNED BY AIR IN TANKS FORCES OIL BACK INTO CYLINDERS CHM THRU RACK PULLINQ- AND HOLDINQ LOWER SLIDE DOWN Feb. 5, 1935. A. SEIDEL El AL 1,989,827

I TRIPLE ACTION POWER PRESS Filed May 5, 1934 6 Sheets-Sheet 6 Patented Feta. 5, 193% @FFEAQE TRIPLE ACTION POWER PRESS Application May 3, 1934, Serial No. 723,738

13 Claims.

' This invention relates to power presses of the type having diilerentially operated work-holding and shaping parts, and particularly to presses of the multiple action type in which the shaping operation is divided into successive movements of various shaping parts.

Important objects of the invention are the provision of a simple and eflicient method and means whereby the shaping operation is accomplished with a minimum of stretching at any particular point of the metal worked upon.

Another object of the invention is the provision of positive acting means to control the movement of the shaping parts.

A further object of the invention is the provision of a power press of the above type in which the parts are capable of separate adjustment and are readily accessible for repair.

Other objects and advantages of the invention will become apparent as the description proceeds, reference being had to the accompanying drawings, in which- Fig. 1 is a front elevation, with parts in section, of a power press embodying the present invention, with the blank holding and forming parts in the positions indicated in Fig. 5, with all work shaping dies omitted;

Fig.2 is a side elevation of the press;

Fig. 3 is an enlarged fragmentary section on line 3-3 of Fig. 1;

Fig. 4 is a fragmentary section on line 4-4 of,

- Fig. 3 showing the work-holding and shaping parts in one position;

Fig. 5 is a view similar to Fig. 4, showing the work-holding and shaping parts in another position;

Fig. 6 is a motion diagram of the work-engaging parts;

Fig. 7 is an enlarged fragmentary section on line '7'l of Fig. 1;

Fig. 8 is a similar section on line 88 of Fig. 3;

Fig. 9 is a fragmentary sectional view similar to Fig. 3 showing a modified form of the lower slide operating mechanism; and Fig. 10 is a section on line 1010 of Fig. 9.

Referring to the drawings, and particularly to Fig. 1, 1 designates the press frame which includes the two spaced uprights 1 connected at their tops by the top crown piece 1 and near their lower ends by the bed 1. A bolster 2 is fixed to the bed between the uprights.

A blank holder 3, comprising the customary slide and removable work engaging part, is mounted above the bed and bolster forvertical reciprocatory movements between the suitable guides 4 secured to the respective frame sides 1, and has a vertical opening therethrough in which an upper plunger 5 is mounted, also for vertical reciprocatory movements and to which is attached the main upper shaping die 5*.

Instead of the usual single lower plunger, the present invention comprehends the division of this lower forming mechanism into a plurality of similar, individually adjustable units. Each unit is spaced from the next adjacent unit by a cross member 6 which extends from front to back between the sides of the bed 1 and which serves to reinforce the lower part of the press. In the embodiment shown the member 6 is cast integrally with the bed. Each unit of the lower forming mechanism includes an outer slide 7, operating in vertical guides in the bed, and an inner lower plunger 8, the latter being reciprocated within the outer slide on suitable guides by the usual crankshaft 9.

In the embodiment shown two crank-arms 10 and 11 are provided for each lower plunger was to prevent side thrust due to an unequally distributed load on the plunger. It will be obvious, of course, that a single crank-arm may be substituted for the two shown on each unit. The upper end of each pitman has an adjustable connection 12 with the plunger head. This connection itself is conventional and need not be minutely described. However, it will be seen that by separately adjusting each unit of the lower shaping mechanism, the press is made readily adaptable to various types of work, since, in effect, one part of the lower plunger may be raised or loweredindependently of the rest so that the top of one plunger may be raised above the next adjacent one. Instead of providing a single crown to support the crankshaft 9, a separate crown piece is provided for each unit so that repairs to any unit may be made without dismantling the entire base. The separate crowns 13 and 14 are bolted to the bed and to the side frames.

The ends of the crankshaft 9 project outwardly beyond the bearings 15 therefor in the side frame and each has a gear 16 fixed thereto and adapted to be driven from any suitable source of power which is common to both ends of the press.

The blank-holder operating mechanism in the present instance includes, at each side of the press, a pitman or connecting rod 20, attached at its lower end to an eccentric 21 carried by the main crank-shaft 9 on the outer side of the respective gear 16, and at'its upper end to a slide block 22 mounted for vertical reciprocatory movements in a guide 22 Each block 22 at its upper. end is connected by a suitable linkage mechanism 23, 24, 25 to a connecting link 26 as best shown in Fig. 2. It will be seen from Figs. 1 and 2 that the connections from each slide block to the blank-holder on the respective side are duplicated in the front and rear of the press so that all four corners of the blank-holder are driven equally. The connecting link 26 con nected at its upper end to an arm 27 carried by a toggle shaft 28, which is journalled in the frame. The toggle shaft 28 drives the adjacent side of the blank-holder through toggle arms 29 and lines 29 the latter having an adjustable connection with the blank holder at its lower end.

The upper plunger 5 is also driven from the crankshaft 9, the mechanism being duplicated at each side of the press and including, at each side, an eccentric 30, which is carried by the crankshaft at each end thereof at the inner side of the respective gear 16. A pitman 31 is driven by the eccentric and is connected at its upper end to a slide block 32 mounted for vertical reciprocatory movements in the frame inside the slide block 22. An arm 33 is carried by the slide and is connected by a link 34 to one end of a bellcrank lever 35 which is pivoted in the frame on a bearing shaft 35. The other end of the bellc-rank lever 38-is connected by a link 39 to a rocker arm 40 pivoted in the frame and having a toggle connection with pitman 41. The pitmanAlis the final drive link for the upper plunger and has an adjustable connection therewith.

At the bottom of the press, as best disclosed in Fig. 3, the lower slide '7 is guided for vertical reciprocatcry movements in the frame by the bed -1 and by the'bed reinforcing member 5. The

lower plunger 8 reciprocates within the lower slide and is guided in its movements thereby.

In one embodiment of the invention the lower slide control ,mechanism includes hydraulic means for raising the slide and a positive means for lowering it. As shown in Figs. 3, '7 and 8, the hydraulic raising means comprises cylinders 50 at each corner of each slide '7, which are disposed pistons 51, connected to the slide by piston rods 52. Oil or any other suitable liquid is forced into the cylinders from storage tanks 53 which are conveniently'disposed one at the front and one at the rear of the press between the sides thereof. In order to for-2e oil into the cylinders 50 the top of the storage tanks 53 are connected with a source of air pressure supply by a pipe 53 in which suitable pressure regulating valves 53 and check valves 53 are located. Thus a constant pressure of air is kept on the oil tending to force it out of the tanks info the cylinders 50. Oil conduits 54 connect each tank to the cylinders 50 on the adjacent side of the press, suitable communicating lines being provided for each cylinder. Interposed in each line is a fluid control valve 55, as shown in Fig. '7, which is adapted to close the port 56 in the side of the cylinder 50. The valve stem is directly connected with a pis ton '7, which is adapted to be reciprocated by pneumatic pressure or otherwise within a cylinder 58. Suitable fluid connections are made with the cylinder through pipes 59, the fluid flow being reversed in the pipes depending on the period of the cycle. As shown in Fig. 8, the air pressure in cylinder 58 is controlled by a valve mechanism comprising valves 60 and 60 which are actuated alternately by cams 61 and 62 carried by a disc 1 63 on the crankshaft 9, one cam being aligned with a follower on each valve, which latter are forms an incompressible support for the outer slide. When the slides '7 are to be lowered the associated valves 55 are opened and the liquid in the cylinders 50 forced back' into the tanks.

53. To accomplish this, a cam '75 is provided on the crankshaft 9, centrally of each lower unit. A follower 71 is journalled in a central rack member '72, which is reciprocable within a slotted guide block '73 fixed to the crown 13. On each side of the central rack member is a pinion '74, journalled in the fixed guide block. The guide block is further slotted vertically to receive and guide a pan of reciprocating connecting rods '75, which carry corresponding rack teetli adjacent their lower ends to engage the pinions '74, and which are fixed to the slide '7 at their upper ends. The connecting rods '75 are passed through guides '76 in the plunger 8.

It will be seen that by the mechanism just described that as the cam 70 rotates, the follower 71 will ride up on the lobe of the cam, thus raising the central rack '72, rotating the pinions '74 lower the slides 7, so that all of the hydraulic apparatus may be omitted. Such a modification is shown in Figs. 9 and 10 and includes a cam block 100 carried by the crankshaft 9 in place of the cam '70. The cam block is provided on each side face with similar grooves 101 having a configuration identical to the periphery of the cam 70. In this instance the follower comprises a bifurcated yoke 102 having at each lower end an inturned portion 103 engaging in the grooves. It will be readily appreciated that the yoke will be moved upwardly or downwardly by the cam block 100 and will impart reversed movements to the slide '7 through the racks and pinions '72, '74 and '75. Suitable guides 104 are provided in the guide block '73 so as to resist any tendency of the yoke to move laterally.

The work forming means constitutes a particularly important part of the present invention, and includes, as shown in Figs. 4 and 5, the blarsk holder 3, the upper plunger die 5,'a main or stationary lower die 80, a redrawing die 81, and a gathering die 82. The actual shaping of the redraw is accomplished by the redraw die 81, which is mounted for vertical reciprocation in the lower die 80 and is positively actuated in one direction by the lower plunger 8 through the medium of push rods 83. These rods are passed through suitable holes in the bolster 2 and are pushed upward by the lower plunger, as shown in Fig. 5. When the push rods retract the redraw die -81 returns by gravity to normal lowered position.

It has been found that in the formation of offset panels by a press of this type the redrawing operation is frequently accompanied by a tearing of the metal adjacent to the offset due to excessive stretching of the material. To remedy this the present invention provides a means to gather material for the redrawing operation in the center of the panel during the drawing step. Thus, a doomed gathering die 82 is mounted for vertical reciprocation within the redraw die 81 and is positively moved upwardly by the lower slide 7 through the medium of push rods 84. These rods rest at their lower ends on the slide 7 and pass upward thru guide openings in the bolster 2 and registering portions of the dies 80 and 81 and hear at their upper ends against the bottom of the die 82. By the action of this member 82, material for the redrawing step is gathered in the shape of a dome to be subsequently utilized by the redraw die 81 in its drawing operation.

The operation of the press may well be described with reference to the motion diagram of Fig. 6. Starting a cycle at 0, it will be seen that the blank-holder 3, the motion of which may be followed in line A, and the upper plunger 5, represented in line B are in their upper, or retracted positions. Also at this point the lower plunger 8, represented by line C is nearing the lowermost point of its stroke, while the lower slide 7, as shown by line D, is stationary in its upper position. The blank-holder 3 is first moved down to hold the material, and has a considerable dwell in its stroke so that it remains down in place through a period starting at point E in the diagram. The upper plunger lowers to engage the material shortly after the blank-holder and continues to move to the bottom of itsstroke, designated by point F. During this main drawing operation the domed die 82 has been stationary in its upper position, so'that the several parts are in the position shown in Fig. 4 with the material for the redrawing operation gathered over the dome. When the cycle has reached point G, the cam 61 opens the exhaust valve so as to relieve the air pressure back of the pistons 5'7. The cams 70 now move to cause the racks '72 and '75 and pinions 74 to pull the slides 7 down. So long as the follower '71 is on thelobe of the cam' '70 the slide 7 will dwell for a period represented by H-I. As the gathering die 82 moves away from the material, the redraw die 81 is forced upwardly by the lower plunger 8 so that the material previously gathered by the die 82 is drawn outwardly, or straightened, to the position shown in Fig. 5, which discloses the redraw die in its final drawing position, represented by the peak of line C, Fig. 6. This completes the forming of the material, so that the only remaining steps are those of stripping the material from the dies and returning the parts to the initial position.

The stripping of the material from the upper die 5 is accomplished by moving the upper plunger away from the material before releasing the blank-holder. For comparative purposes, the line representing the cycle of the blank-holder has been projected down to coincide in part with the graph of the upper plunger as shown in dotted lines. It will be seen that the upper plunger moves away from the material at point J, and, since the blank-holder continues its dwelluntil point K the material will be held in place momentarily so that any adherence to the upper die will be prevented. Lastly it will be seen that at point I the follower '11 rides ofl of the lobe of the cam '70, leaving the lower outer slide free to be forced upwardly by the oil which is pneumatically forced out of -the tanks 53 into the cylinders 50. When the lower slide has returned to its upper position designated at L, the cam 62 engages its valve actuating follower and admits air to the rear of the cylinders 58, moving the hydraulic valve 55 to seating position and retaining it there until the pressure is relieved during the next cycle of the press. cycle of operations has been completed the gathering die 82 will have returned to its uppermost position, shown in Fig. 4, and may act to strip the formed work from the lower die 80.

It will be understood that no novelty is claimed for the blank-holder and die combination apart from the inclusion therein of the gathering die 82, and that the use of such die is not restricted to a combination or arrangement of blank-holder and dies as shown, as this is merely illustrative of one embodiment of the invention. This feature of the invention, which is of great value in drawing work of this character, contemplates not only means. in combination'with panel drawing dies, for gathering surplus stock with a predetermined area of the material for use in the subsequent panel drawing operation, but also to a method for accomplishing this.

What we claim is:-

1. In a power press, the combination with drawing dies, redraw dies, and mechanism for operating said dies in predetermined sequence, of gathering means operating within at least one of the drawing dies, and mechanism for operating said gathering means to gather surplus material in a predetermined portion of the blank prior to and for the redraw operation.

2. In a power press, the combination with drawing dies, redraw dies, and mechanism for operating said dies in predetermined sequence, of

.means for bulging a predetermined portion of the work blank to gather surplus material therein, and mechanism for imparting predetermined timed movements to said means to operate on the blank substantially simultaneously with the drawing operation and to disengage the blank prior to the redraw operation.

3. In a power press, the combination with drawing dies, redraw dies, and mechanism for operating said dies in predetermined sequence, of a gathering die, and means for operating the gathering die to gather surplus material in a work blank within the area to be redrawn and then to retract such die before the redraw operation. 1

4. In a power press, the combination with drawing dies, 9. redraw die within a portion of the drawing dies, and mechanism for operating said dies in predetermined sequence, of a gathering die operating within the redraw die, and mechanism for actuating said gathering die to gather surplus material in the work blank within the area to be redrawn and then to recede prior to the redraw operation.

5. In a power press, the combination with blank holding means, drawing means, redraw means, and mechanism for operating said several means in predetermined sequence, of means for gathering surplus material within the area of the blank to be redrawn, and mechanism operating in predetermined timed relation to said first three means whereby a gathering operation' is imparted to the gathering means between the initial engagement oi. the blank by the blank holding means and the operation thereon of the redraw means.

6. In a power press, the combination with mechanism operable to sequentially hold, draw and redraw a work blank, of gathering means operable on the blank to gather surplus material It is thusseen that by the time a e therein within the area to be redrawn, and control mechanism for said means causing it to have a gathering action on the blank intermediate the initial engagement thereof by said first mechanism and the redraw operation, and then to disengage the blank. I

7. In a power press, the combination with drawing dies, redraw dies, and respective means for operating said dies, of means for gathering surplus material within a predetermined portion of a work blank before the action on the blank of the redraw dies, means for moving said gathering means to and cause it to dwell in gathering position prior to the redraw operation, and means for retracting the gathering means from gathering position during the redraw operation.

8. In a power press, the combination with main drawing die-s, redraw dies, and mechanism for operating said dies in predetermined sequence, of a gathering die operating within the redraw dies, means for moving the gathering die to gathering position prior to the redraw operation, and means for retracting the gathering-die from gathering position prior to the redraw operation and retaining it in such position during said operation.

' 9. In a power press, the combination with blank holding means, upper drawing means and mechanism for operating both of said means in predetermined sequence, of lower gathering means to gather material within the area of the blank to be redrawn, redrawing means, means to operate said lower gathering means, and a plurality of independently adjustable lower plungers to operate said redrawing 'means.

10. In a power press, the combination with blank holding means, upper drawing means, a crankshaft and mechanism for operating both of said means in predetermined sequence from said crankshaft, of lower gathering means and redrawing means, a plurality of lower slides to operate said gathering means, hydraulic means to raise said slides, means actuated by said crankshaft to lower said slides, and a plurality of independently adjustable lower plungers operated by said crankshaft to actuate said redrawing means.

11. In a power press, the combination with blank holding means, upper drawing means and mechanism for operating both of said means in predetermined sequence, of lower gathering means to gather material within the area of the blank to be redrawn, redrawing means, lower slides to operate said lower gathering means, and lower plungers mounted for reciprocation within said lower slides to operate said redrawing means.

12. In a power press, a frame, a blank holder, an upper plunger, a lower plunger andalower slide mounted in said frame, a crankshaft mounted in the frame, means to drive said blank holder from said crankshaft, means to drive said upper plunger from said crankshaft, means to drive said lower plunger from said crankshaft, hydraulic means to raise said lower slide, and means actuated by a cam carried by said crankshaft to withdraw said lower slide.

13. In a power press, a frame having a bed, a blank holder and an upper plunger mounted in the frame above said bed, a lower plunger and a lower slide mounted one within the other for reciprocatory movements through said bed, a crankshaft mounted in said frame, connections between said crankshaft and said lower plunger, separate connections between said crankshaft and the blank holder and upper plunger for reciprocating the same from rotation of the shaft and causing them to dwell in blank engaging position during the blank shaping movement of said lower plunger, a die operated by said lower slide, means to maintain said die in material engaging position during the downward stroke of said blank holder and said upper plunge-r, means to retract said lower slide and said die, said means being operated from the crankshaft, and operative only during the period when said lower plung er is in material shaping position.

ADOLPH SEIDEL. MEREDITH R. HA TCH. 

